
import java.util.Scanner;

public class TestG {
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        while(sc.hasNext()) {
            int n=sc.nextInt();
            int s=1;
            for(int i=1;i<=n;i++) {
                int a=sc.nextInt();
                if(a%2==1)
                    s=s*a;
            }
            System.out.println(s);
        }
    }
}